The Atlantic bluefin tuna, also known as the ‘giant tuna’, has returned to the North Sea after a half-century absence. It had disappeared in the 1960s due to overfishing. Scientists are now observing its reintegration, thanks to better fisheries management, according to the Flanders Institute for the Sea (VLIZ) on Tuesday.
The species had not been sighted in the North Sea since 1963. Since then, it has been observed several times further north. A network of European scientists has analyzed the movements of these fish using transmitters and tags.
Warming Seas
Recently, a Danish institute reported hundreds of bluefin tunas at the junction of the Baltic and North Seas. « These studies have shown that bluefin tunas use both seas as feeding grounds, especially in summer and autumn. » This fish can measure up to 3.5 meters and weigh 750 kg. The species has long been considered threatened, but it is now on the road to recovery thanks to reduced fishing quotas and efforts to combat illegal fishing. However, scientists remain cautious, as the sustainable re-establishment of the species will depend on the success of its reproduction in the Mediterranean. « Since the animals returning today to the North Sea belong only to a few age classes, they are particularly vulnerable to the pressures exerted by fishing. »
Source: rtbf
